1. Field of the Invention
This invention relates to a drawing processing apparatus used in the fields of OA (office automation) and CAD (computer-aided design), and to a drawing processing technique for writing a character string or character strings within a block having the shape of a rectangle, an ellipsoid, a lozenge or the like when preparing a block diagram, a flowchart or the like.
2. Description of the Related Art
As the method for writing a character string or character strings within a symbol or a block in a flowchart or a block diagram, several methods have been considered in the DTP system and the drawing system.
(1) In one method, as shown in FIG. 11, the user initially assigns the number of characters in one line using a character input column 200 so that the width of a character string does not exceed the width of a block 201.
If the number of characters exceeds the block width, protrusion in the direction of the block width is prevented by performing automatic line feed and preparing a character string having a constant width. However, the user must perform the positioning of the character string and the block using an editing command.
Furthermore, if the character string has protruded in the direction of the block height, it is necessary to take appropriate measures, such as changing the size of the block.
(2) Another method may also be considered in which, as shown in FIG. 12, when preparing a character string within a block made of, for example, a rectangle, an ellipsoid or the like, a character frame (box) 211 having the same size as the circumscribed rectangle of an object block 210 is automatically prepared at the position of the rectangle, and a processing named "box setting" is performed within the box.
The main function of box setting is a layout function, such as automatic line feed of the character string at the right end of the box, centering, shift to the right or left and justification of each line, centering in the vertical direction, and shift to the upper or lower position, relative to the box.
The processing of box setting is also performed at the moment of the editing operation of the character string and the change of the box size.
Furthermore, by maintaining the relation between the block and the character string, both the box and the character string can conjointly move at the moment of executing an editing command, such as movement, deletion, rotation or the like.
(3) A similar method has also been disclosed in Japanese Patent Public Disclosure (Kokai) No. 62-267858 (1987) (Applicant: NBC Corporation). As shown in FIG. 13, this method only deals with a rectangular block, and the block itself corresponds to the box in the above-described processing. Accordingly, if the block width has been changed, the position for automatic line feed is renewed so that the character string spreads over the entire block width.
In the above-described case (1), although the width of the character frame (the number of characters) may be arbitrarily set, the relation between the character string and the block is not administrated by the system side. Hence, the user must perform the positioning of the character string and the block, and a processing to dissolve protrusion in the direction of the block height.
In the above-described case (2), the box corresponding to the character frame is automatically set only when the character string is written in a blank block, and only the mutual position relationship is thereafter maintained. Hence, the user must change the size of the box 211 when the block size has been changed to the size (210').
On the other hand, if the character string has protruded from the block when the user changed the box size to a desired size, it is necessary to change the block size in accordance with the amount of protrusion.
Furthermore, the mutual position of the character string relative to the block is maintained only for one character string. Hence, when a plurality of character strings are dealt with within the block, the above-described function to maintain the position relation is not used, and the setting of the box size and positioning are performed for each character string.
Also in the above-described case (3) of Japanese Patent Public Disclosure (Kokai) No. 62-267858 (1987), since the number of character strings which can be dealt with within the block is limited to one, it is impossible to deal with a plurality of character strings having different character sizes and spaces within the block.
Furthermore, since the character string is expanded over the entire block width (221), it is impossible to perform automatic line feed in a line width desired by the user (222).
As described above, although there have been devised various methods for writing a character string or character strings within a block, there has not been realized yet a function to dissolve protrusion or to perform layout processsing for a plurality of character strings within a block. Hence, there is enough room for improvement.